Mechanism for axially reciprocating a distributing cylinder in a printing machine



Oct. 24, 1967 F. BoHA ETAL 3,348,480

MECHANISM FOR AXIALLY RECIPROCATING A DISTRIBUTING CYLINDER IN A PRINTING MACHINE Filed May 12, 1965 A v v myEzyToRs fra /1775M! 30A 616 Jad/J/ay- BY 50M741 Wan/ 4 0 United States Patent 3,348,480 MECHANISM FOR AXIALLY RECIPROCATING A DISTRIBUTING CYLINDER IN A PRINTING MACHINE Frantisek Bohac, Krtiny, and Ladislav Burda, Brno, Czechoslovakia, assignors to Adamovsk Strojirny, narodni podnik, Adamov, Czechoslovakia Filed May 12, 1965, Ser. No. 455,100 Claims priority, application Czechoslovakia, May 14, 1964, PU 2,786/64 3 Claims. (Cl. 101349) ABSTRACT OF THE DISCLOSURE A mechanism for axially reciprocating an ink distributing cylinder in a printing press in which a coaxial annular cam on the cylinder is resiliently urged against a ball received in a cam groove extending about the cylinder axis in a plane obliquely inclined relative to the axis, the ball making point contact with the side Walls of the groove which converge inward of the groove at an acute angle so that the cylinder is axially reciprocated once during more than two revolutions thereof.

Background of the invention This invention relates to a mechanism for axially reciprocating a distributing cylinder for ink and the like in a printing machine while the cylinder is being rotated.

Known reciprocating mechanisms for distributing cylinders are either complex, or they cause axial movement of the cylinder which is very fast and induces harmful vibrations in the machine if the cylinder is rapidly rotated.

Summary of the invention The reciprocating mechanism of this invention provides cooperating cam means on the distributing cylinder and on the stationary supporting structure of the machine including a first cam member formed with an annular groove about the cylinder axis which has two side Walls angularly converging inward of the groove. A ball member is partly received in the groove and makes simultaneous I point contact with the side walls.

A second cam member has an annular face about the cylinder axis in axial alignment with groove of the first cam member. The two cam members are fixedly fastened to the cylinder and to the supporting structure respectively, and are resiliently urged axially toward each other for rolling engagement between the ball member and annular face of the second cam member, the annular face and the groove providing cam tracks for the ball member, at least one of the tracks extending in a plane obliquely inclined relative to the cylinder axis.

This arrangement permits the distributing cylinder to be reciprocated only once during more than two revolutions thereof so that the tendency of the machine to vibrate is reduced. The ball member cannot slip in the cam groove even if the diameter of the distributing cylinder is relatively small and the required axial movement is relatively great.

Brief description 0 the drawing In the attached drawing,

FIG. 1 shows a mechanism of the invention in section on the axis of the distributing cylinder; and

FIG. 2 shows a detail of FIG. 1 on a larger scale.

Description of the preferred embodiment The drawing shows only as much of a printing machine as is needed for an understanding of this invention. A

3,348,480 Patented Oct. 24, 1967 shaft 4 is journaled in the supporting machine frame 1 by means of ball bearings 3 and carries a drive gear 2. An ink distributing cylinder 5 is rotatably and axially movably mounted on the shaft 4. A coupling pin 11 connects the cylinder to the shaft for joint rotation, but permits relative axial movement.

The side walls of the groove 7 converge inward of the groove at an acute angle so that a steel ball 8 which is partly received in the groove makes only point contact with the side walls. The dimensions of the ball and of the groove are such that the distance b between the center of the ball 8 and a line connecting the two points of contact between the ball and the groove walls is less than one half of the ball radius a.

A spring 10 interposed in the hollow cylinder 5 around the shaft 4 urges the ring 9 toward the ring 6, thereby holding the ball 8 in rolling engagement with the cam tracks provided by the groove 7 and the annular face of the ring 9.

The illustrated mechanism operates as follows:

While the shaft 4 and the cylinder 5 are rotated by the gear 2, the ball 8 rolls along the cam tracks and thereby shifts the cylinder 5 axially toward the right against the We claim: 1. In a printing machine having a stationary support, a distributing cylinder mounted on said support for rotation about the axis thereof, and means for axially reciprocating the cylinder during said rotation, the improvement in the reciprocating means comprising:

(a) cooperating ring means on said support and on said cylinder, said ring means including (1) a cam member formed with an annular groove about said axis, said groove having two sidewalls .angular'ly converging inward of said groove, 7

(2) a ring member having an axially projecting annular face about said axis and thus being in axial alignment with said groove, and terminating at a plane front face axially facing said groove, said annular face converging toward said front face,

(3) a ball member having a portion received within said groove in simultaneous three-point contact with said side walls and said front face,

(4) said cam member and said ring member being fixedly fastened to said support and said cylinder, respectively, and

(b) yieldably resilient means urging said cam and ring members axially toward each other for rolling engagement of said ball member between said side Walls and said front face in said three-point contact.

2. In a printing press as set forth in claim 1, said side Walls converging at an acute angle.

3. In a printing press as set forth in claim 1, the distance of the center of said ball member from a line connecting the respective points of contact of the ball member with said side Walls being smaller than the radius of said ball member.

4 References Cited UNITED STATES PATENTS 1,040,170 8/1912 Dietrich 101-337 5 1,041,569 10/1912 Bade 7456 1,294,961 2/1919 Schultz 101-348 3,110,253 11/1963 Du Bais 101348 ROBERT E. PULFREY, Primary Examiner.

10 F. A. WINANS, Assistant Examiner. 

1. IN A PRINTING MACHINE HAVING A STATIONARY SUPPORT, A DISTRIBUTING CYLINDER MOUNTED ON SAID SUPPORT FOR ROTATION ABOUT THE AXIS THEREOF, AND MEANS FOR AXIALLY RECIPROCATING THE CYLINDER DURING SAID ROTATION, THE IMPROVEMENT IN THE RECIPROCATING MEANS COMPRISING: (A) COOPERATING RING MEANS ON SAID SUPPORT AND ON SAID CYLINDER, SAID RING MEANS INCLUDING (1) A CAM MEMBER FORMED WITH AN ANNULAR GROOVE ABOUT SAID AXIS, SAID GROOVE HAVING TWO SIDE WALLS ANGULARLY CONVERGING INWARD OF SAID GROOVE, (2) A RING MEMBER HAVING AN AXIALLY PROJECTING ANNULAR FACE ABOUT SAID AXIS AND THUS BEING IN AXIAL ALIGNMENT WITH SAID GROOVE, AND TERMINATING AT A PLANE FRONT FACE AXIALLY FACING SAID GROOVE, SAID ANNULAR FACE CONVERGING TOWARD SAID FRONT FACE, (3) A BALL MEMBER HAVING A PORTION RECEIVED WITHIN SAID GROOVE IN SIMULTANEOUS THREE-POINT CONTACT WITH SAID SIDE WALLS AND SAID FRONT FACE, (4) SAID CAM MEMBER AND SAID RING MEMBER BEING FIXEDLY FASTENED TO SAID SUPPORT AND SAID CYLINDER, RESPECTIVELY, AND (B) YIELDABLY RESILIENT MEANS URGING SAID CAM AND RING MEMBERS AXIALLY TOWARD EACH OTHER FOR ROLLING ENGAGEMENT OF SAID BALL MEMBER BETWEEN SAID SIDE WALLS AND SAID FRONT FACE IN SAID THREE-POINT CONTACT. 